Deep-sea Detectives

SHARE THIS:

16 of 18

The scientists published their work, which was funded by the National Science Foundation, in the journal Nature Geoscience in November, 2010. But publication didn’t end the story. If the process they observed is more widespread, that raises another question: Just how much carbon is being released into the water?

Scientists have thought that once carbon from organic detritus, carbonate shells, and other sources sinks and is deposited on the seafloor, it is sequestered there for a few hundred thousand years. But the researchers estimate that the process seen in the Guaymas Basin could drive as much carbon out of the sediments as goes into them. That means deposits of carbon in seafloor sediments may not be as permanent as previously thought, and we may need to re-think suggestions to use the deep ocean as a repository for excess atmospheric carbon.

“We could be burying a lot less carbon than we think if this is going on, because these particular sediments are extremely organically rich,” said Seewald (above). “There’s a lot of carbon in this basin. And if it’s going to be released back to the ocean or atmosphere, there’s a huge impact.”

Lizarralde said seafloor organisms would recapture some of the released carbon, but a substantial amount escaping to the ocean could reduce the pH of seawater and have impacts on marine life. If some carbon made it all the way to the atmosphere in the form of carbon dioxide, a greenhouse gas, it could play an unsuspected role in climate change.